Occlusion 2

Question 1

First step in assessing occlusion?

Answer 1

Mark tooth with articulating paper - 2 colours

One colour for static occlusion (tap) one for dynamic occlusion (grind)

Hold them between dried teeth with millers forceps

Question 2

When should you mark teeth?

Answer 2

Before prepping a tooth
Before removing restoration

After placing a crown
After placing a restoration

Question 3

What are functional cusps, where found?

Answer 3

Cusps that occlude with opposing teeth in the ICP

Lingual cusps of maxillary posteriors

Buccal cusps of mandibular posteriors

Question 4

What are non functional cusps?

Answer 4

Cusps that do not occlude during ICP

Buccal cusps of maxillary posterior

Lingual cusps of mandibular posterior

Question 5

Define anterior open bite

Answer 5

Lack of vertical overlap of anterior teeth when posterior teeth in full occlusion

Question 6

Define posterior or lateral overbite

Answer 6

Failure of contact between posterior teeth when teeth in full occlusion

Question 7

Define cross bite

Answer 7

One or more teeth abnormally malpositioned buccal, lingual or labially with reference to opposing teeth

Question 8

Define overjet

Answer 8

Relationship of maxilla / mandiblar teeth in the horizontal plane

Question 9

What is overbite

Answer 9

Vertical overlap of the incisors

Question 10

What is the gold standard dynamic occlusion

Answer 10

Canine guidance

No working / non working side contacts other than canines

No protrusive interferences and only canines and incisors should contact during protrusion

Question 11

What are occlusal interferences?

Answer 11

Undesirable tooth contacts that may cause mandibular deviation during closure to ICP, or hinder smooth passage to and from ICP

Question 12

Types of occlusal interference?

Answer 12

Working side

Non working side

Protrusive

Question 13

What is a working side occlusal interference?

Answer 13

Posterior contacts on the working side on lateral deviation of mandible

Question 14

What is a non working side occlusal interference?

Answer 14

Cusps contacting in posterior teeth on non working side on mandibular lateral deviation

Question 15

What is a protrusive occlusal interference

Answer 15

Any posterior contact during protrusion when the condyle moves forwards, downwards along the articular eminence

Question 16

Why should posterior contacts be avoided during laterals movements?

Answer 16

Teeth designed to absorb heavy contacts along long axis of tooth, not on lateral movement

Posterior contacts can cause occlusal trauma and undesirable tooth movement

Muscles get a rest if there are no posterior occlusion, if there are then muscles are mostly always in use causing TMJ issues, muscular hypertrophy

Question 17

What are the two components of bruxism?

Answer 17

Eccentric - parafunctional grinding of teeth

Centric - static clenching of the Jaws

Question 18

Clinical signs of bruxism?

Answer 18

Tooth wear

Fractured restorations

Tooth migration

Increased tooth mobility due to widening of PDL

Muscle pain or fatigue

Headache

Pain and stiffness in TMJ

Question 19

What are the classifications of occlusal trauma?

Answer 19

Primary - intact periodontium

Secondary - reduced periodontium

Fremitus - palpable or visible tooth movement when subject to occlusal forces